Re: Transrapid abandons Sydney-Canberra

[Hans Kraus <hans.w.kraus@siemens.at>]

David Bromage wrote:
> 
> Jon Bell wrote:
> >
> > In article <7o8ro4$qn0$1@xs4.xs4all.nl>,
> > Maarten Deen <mdeen@xs4.xs4all.nl> wrote:
> > >
> > >I wonder if that's true. Wheel-rail friction is eliminated whith a maglev
> > >system. Doesn't this mean less friction overall?
> >
> > Yes, but at high speeds air friction tends to dominate everything else.
> 
> Air resiatance is proportional to the cube of the speed.
> [...]

Air resistance is proportional to the _square_ of the speed.
Energy (for overcoming air resistance) is proportional to the
resistance and so too proportional to the square of the speed.
Power is proportional to the cube of the speed (you need to spend
the energy in a shorter time).

MfG., Hans Kraus